Managers 2.0 must learn to be what Philip Kotter has called “leaders”. I.e. they must learn to lead change. This implies that they must learn to use people as clever human beings. Above all they must learn to manage groups. No longer consider companies as sets of disconnected individuals. Groups and societies have implicit rules (ethnologists’ “culture”). Their members, more or less consciously, follow these rules. Acting on them instantly transforms the organisation (Jay Forrester’s “leverage change”). What scientists call “complexity” is all about these properties of groups or “social networks”. Web 2.0 has started to use them.